Question

Cast iron has the maximum percentage of carbon
(A) True
(B) False

Answer 1

To answer this question, you must recall the types of iron formed during the extraction of pure iron metal from its ore. Cast iron is an impure form of iron formed in the process of its extraction. The extraction of iron metal from its ore is generally carried out using the process of smelting.

Complete step by step solution:
Cast iron is a form of an alloy formed by iron and carbon. It is the most impure form of iron obtained after the process of smelting is completed in the blast furnace. It has the highest percentage of carbon of all forms of iron containing more than 2 percent of carbon as an impurity but not more than 5 percent. It also contains around 2 percent of other impurities like silicon, manganese, phosphorus and sulphur. So, the given statement is true.
The correct answer is A.

Additional information:
Smelting is the process of the extraction of a metal obtained either in the elemental form or in the form of a simple compound, from its ore by heating it to temperature higher than its melting point in the presence of oxidizing agents like air, or in the presence of reducing agents like coke. Various primary steps are carried out for the purification of the ore as much as possible before it is subjected to smelting. In the smelting process of an oxide, namely iron oxide, the ore is heated to a high temperature. The oxygen combines with the carbon present in the fuel and escapes the mixture as carbon monoxide or carbon dioxide. Other impurities that are known as gangue are removed by the addition of a flux which combines with the former to form slag.

Note:
The purest form of iron obtained by conventional methods is wrought iron. Wrought iron is almost 99% pure iron. It contains only around $0.1$ percent of carbon and only $0.35$ percent of other impurities. 100% pure iron metal can be obtained by the process of electrolysis.